Recording Device, Recording Method, and Computer Program

ABSTRACT

A recording apparatus with a device for recording information onto a medium, provided with: (i) a first layer irradiated with laser light to record information on a first area; and (ii) a second layer irradiated with laser light through the first layer and having a second area whose edge on an inner circumferential side corresponds to an edge on an outer circumferential side of the first area; and a controlling device for controlling the recording device to pre-record, into an area portion of the first area, other than an area portion having a size corresponding to a tolerance length, which indicates an acceptable range of a relative position shift between an address defined on the predetermined position in the first layer and an address related to the predetermined position in the second layer, with the edge on the outer circumferential side of the first area as a starting point.

TECHNICAL FIELD

The present invention relates to a recording apparatus and method, suchas a DVD recorder, and a computer-readable recording medium recordingthereon a computer program which makes a computer function as therecording apparatus.

BACKGROUND ART

In an information recording medium, such as a CD-ROM (Compact Disc-ReadOnly Memory), a CD-R (Compact Disc—Recordable) and a DVD-ROM, forexample, as described in patent documents 1 and 2, etc., there is alsodeveloped an information recording medium, such as a multi-layer typeoptical disc, in which a plurality of recording layers are laminated orpasted on the same substrate. Then, on an information recordingapparatus, such as a DVD recorder, for performing the recording withrespect to the dual-layer type (i.e., two-layer type) optical disc,laser light for recording is focused on a recording layer located on thefront (i.e. on the closer side to an optical pickup) as viewed from theirradiation side of the laser light (hereinafter referred to as an “L0layer”, as occasion demands) to thereby record data into the L0 layer inan irreversible change recording method or a rewritable method by heat.Moreover, the laser light is focused or condensed on a recording layerlocated on the rear of the L0 layer (i.e. on the farther side from theoptical pickup) as viewed from the irradiation side of the laser light(hereinafter referred to as an “L1 layer”, as occasion demands), throughthe L0 layer or the like, to thereby record information into the L1layer in the irreversible change recording method or the rewritablemethod by heat. patent document 1: Japanese Patent Application Laid OpenNo. 2000-311346 patent document 2: Japanese Patent Application Laid OpenNo. 2001-23237

DISCLOSURE OF INVENTION Subject to be Solved by the Invention

In such a dual-layer type optical disc, if the data is recorded into theL1 layer, it is necessary to irradiate the laser light through the L0layer. In this case, the record data may be recorded in the L0 layerthrough which the laser light is irradiated with the L1 layer, or maynot be recorded. As described above, the recording state of the L0 layeris not necessarily same, which causes a change in the state of the laserlight with which the L1 layer is irradiated. Thus, a method in which theL0 layer is made in a recorded state to thereby properly record therecord data into the L1 layer is also invented by the inventors of thepresent invention or the like.

However, a position where an address of the L0 layer or the L1 layer isdefined in design does not necessarily match a position where an addressof the optical disc actually manufactured or produced is defined,depending on the quality of a production process. In other words, thereis a possibility that an optical disc is produced in which a certainaddress is actually located away from a radial position where thecertain address is to be located in design. Thus, a predetermined areais not disposed in an intended position in design, which results in atechnical problem that the laser light is not necessarily irradiatedonto the L1 layer through a recording area in the recorded state in theL0 layer.

On the other hand, in the dual-layer type optical disc in an oppositetrack path method, for example, a middle area is located on the mostouter circumferential side of the optical disc. The middle area is tobuffer a changing operation in changing the focus of the laser lightfrom the L0 layer to the L1 layer, and dummy data or the like isrecorded into the middle area upon finalizing. At this time, in order toreduce a time length required for the finalizing, a technology ofrecording in advance (hereinafter referred to “pre-recording”)predetermined dummy data in the middle area in the recording operationhas been invented by the inventors of the present invention. In the caseof a dual-layer type DVD-R, which is one standard of the optical discand in which the development of the standard has been advanced, forexample, an ODTA (Outer Disc Testing Area) for calibrating the power ofthe laser light is provided on the outer circumferential side of themiddle area in each of the L0 layer and the L1 layer. Since the ODTA isused to calibrate the power of the laser light, it is necessary tostrictly define the recording state of the recording area in the L0layer, in using the ODTA of the L1 layer. Specifically, it is definedsuch that the data is not recorded into the recording area of the L0layer which faces or is opposed to the ODTA of the L1 layer which is notused yet. In accordance with this, the pre-recording of the middle areain the vicinity of the ODTA needs to be selectively performed only in aproper recording area. However, due to a shift in the position where thecertain address is defined upon production or the like, as describedabove, the proper recording area cannot be preferably specified. As aresult, there is a technical problem that it is impossible to reduce atime length required for the finalizing because of insufficientpre-recording.

It is therefore an object of the present invention to provide arecording apparatus and method which enable preferable pre-recording toreduce a time length required for the finalizing even on an informationrecording medium having a plurality of recording layers, for example, aswell as a computer-readable recording medium recording thereon acomputer program.

Means for Solving the Subject

(Recording Apparatus)

The above object of the present invention can be achieved by a firstrecording apparatus provided with: a recording device for recordingrecord information by irradiating laser light onto a recording mediumprovided with: (i) a first recording layer which is irradiated with thelaser light to thereby record therein the record information and whichhas a first area in which the record information is recorded; and (ii) asecond recording layer which is irradiated with the laser light throughthe first recording layer to thereby record therein the recordinformation and which has a second area whose s edge on an innercircumferential side corresponds to an edge on an outer circumferentialside of the first area; and a controlling device for controlling therecording device to record pre-information in advance as the recordinformation, into an area portion as being one portion of the firstarea, at least other than an area portion having a size corresponding toa tolerance length, which indicates an acceptable range of a relativeposition shift between an address which is defined on the predeterminedposition in the first recording layer and an address which is related tothe predetermined position in the second recording layer, with the edgeon the outer circumferential side of the first area as a starting point.

According to the first recording apparatus of the present invention, bythe operation of the recording device, it is possible to preferablyrecord the record information including video information, audioinformation or the like, onto the recording medium provided with boththe first and second recording layers. For example, by irradiating thelaser light so as to focus on the first recording layer, the recordinformation is recorded into the first recording layer, while byirradiating the laser light so as to focus on the second recordinglayer, the record information is recorded into the second recordinglayer. In the first embodiment, the first recording layer is providedwith the first area in which the record information is recorded upon thefinalizing (e.g. a middle area, etc., described later, used to buffer achanging operation in changing the focus of the laser light from an L0layer to an L1 layer or from the L1 layer to the L0 layer), in additionto a data area in which the record information, such as the videoinformation and the audio information, is recorded. Moreover, the secondrecording layer is provided with the second area (e.g. an ODTA describedlater, used to calibrate the power of the laser light). The edge on theinner circumferential side of the second area corresponds to the edge onthe outer circumferential side of the first area. The term “correspondto” herein indicates that it exists at a substantially facing or opposedposition in design (e.g. at substantially the same radial position). Inan actual recording medium, it is necessarily located at the facingposition due to an influence, accuracy or the like in the productionprocess.

Particularly, in the first recording apparatus, by the operation of thecontrolling device, the pre-information is pre-recorded into an areaportion as being one portion of the first area, before the finalizing.At this time, the pre-information is pre-recorded into the area portionas being one portion of the first area, at least other than an areaportion having a size corresponding to the tolerance length, from aposition represented by the address of the edge on the outercircumferential side of the first area (i.e. the end edge of the firstarea, which substantially match the edge on the inner circumferentialside of the second area, in design). Specifically, in the case of therecording medium in the opposite track path method, the pre-informationis pre-recorded into the area portion as being one portion of the firstarea, other than an area portion from the position represented by theaddress of the edge on the outer circumferential side of the first areato a position obtained by shifting to the inner circumferential side bythe tolerance length. The “tolerance length” indicates the acceptablerange of the relative position shift between an address which is definedon the predetermined position in the first recording layer and anaddress which is related to the predetermined position in the secondrecording layer. In other words, the “tolerance length” indicates theacceptable range of a relative position shift between an address whichis defined on the predetermined position in the first recording layerand an address which is defined on the predetermined position in saidsecond recording layer. In other words, the “tolerance length” is thesum of: (i) the acceptable range of a position shift in the firstrecording layer between a position where a predetermined address isdefined in design and a position of the predetermined address on theactually produced recording medium; and (ii) the acceptable range of aposition shift in the second recording layer between a position where apredetermined address is defined in design and a position of thepredetermined address on the actually produced recording medium.Moreover, the “pre-information” herein indicates information in generalwhich is recorded in advance into the first area before the finalizeprocess, and the content of the information is not limited. In otherwords, dummy data, descried later, is also one example of thepre-information. On the other hand, information which as some meaning(control information, etc.) also constitutes one example of the“pre-information” as long as recorded before the finalize process.

As described above, according to the first recording apparatus, thepre-information is pre-recorded into the first area, in view of theposition shift of the address caused in the production process of therecording medium or the like. Therefore, in recording the recordinformation into the second area, it is possible to record the recordinformation into the second area through the first recording layer inwhich the record information is unrecorded, without influence of thepre-information which is pre-recorded in the first area. Moreover, it isalso possible to pre-record the pre-information into the first area,without influence on the recording operation of recording the recordinformation into the second area. Thus, upon the finalizing, it ispossible to reduce the size of the record information to be recordedinto the first area, so that it is possible to reduce a time lengthrequired for the finalizing.

Consequently, according to the first recording apparatus, it is possibleto preferably perform the pre-recording in order to reduce a time lengthrequired for the finalizing, even on the information recording mediumhaving a plurality of recording layers.

In one aspect of the first recording apparatus of the present invention,the record information is recorded into the second area through thefirst recording layer in which the record information is unrecorded.

According to this aspect, as described later, for example, it ispossible to preferably calibrate the power of the laser light by usingthe second area. At the same time, it is possible to preferably performthe pre-recording of the first area, as described above, and reduce atime length required for the finalizing.

In another aspect of the first recording apparatus of the presentinvention, the controlling device controls the recording device torecord the pre-information in advance, into an area portion as being oneportion of the first area, other than an area portion having a sizecorresponding to a clearance length which indicates a sum of (i) a spotradius of the laser light on the first recording layer in the case thatthe laser light is focused on the second recording layer and (ii) arelative eccentric shift of the first and second recording layers or anacceptable range of the eccentric shift, in addition to the area portioncorresponding to the tolerance length.

According to this aspect, it is possible to pre-record thepre-information into an area portion as being one portion of the firstarea, in view of the eccentric shift and the size of the spot of thelaser light or the like, in addition to the position shift in theaddress caused in the production process of the recording medium or thelike. Therefore, it is possible to record the record information intothe second area through the first recording layer in which the recordinformation is unrecorded, without influence of the pre-informationwhich is pre-recorded in the first area. At the same time, it ispossible to reduce a time length required for the finalizing.

In another aspect of the first recording apparatus of the presentinvention, the recording apparatus is further provided with a convertingdevice for converting the tolerance length to a recording unit of therecord information, and the controlling device controls the recordingdevice to record the pre-information in advance, into an area portion asbeing one portion of the first area, at least other than an area portionhaving a size corresponding to the tolerance length which is convertedto the recording unit.

According to this aspect, it is possible to recognize the tolerancelength by the recording unit (e.g. ECC block unit) of the recordinformation which is easily recognized or easily handled by therecording apparatus. Therefore, the recording apparatus can recognizethe area portion as being one portion of the first area, preferably andrelatively easily.

In an aspect of the recording apparatus provided with the convertingdevice, as described above, the converting device may convert thetolerance length to the recording unit of the record information, on thebasis of correspondence information which defines a correspondencerelationship between the tolerance length and a size of the recordinformation which can be recorded into an area portion having a sizecorresponding to a predetermined tolerance length.

By such construction, it is possible to convert the tolerance length tothe recording unit of the record information, relatively easily, byreferring to the correspondence information.

In an aspect of the recording apparatus in which the tolerance length isconverted to the recording unit on the basis of the correspondenceinformation, as described above, the converting device may convert thetolerance length to the recording unit of the record information, on thebasis of at least one of a plurality of correspondence information, inaccordance with at least one of a type of the recording medium and aposition of the first area on the first recording layer.

By such construction, it is possible to convert the tolerance length tothe recording unit of the record information, relatively easily, withoutinfluence of a difference in the type of the recording medium and adifference in the arrangement of the first area, yet depending on eachdifference.

In an aspect of the recording apparatus in which the tolerance length isconverted to the recording unit on the basis of the correspondenceinformation, as described above, the recording apparatus may be furtherprovided with a storing device for storing the correspondenceinformation.

By such construction, it is possible to convert the tolerance length tothe recording unit of the record information, relatively easily, byreferring to the correspondence information stored in the storingdevice.

In an aspect of the recording apparatus in which the tolerance length isconverted to the recording unit on the basis of the correspondenceinformation, as described above, the converting device may convert thetolerance length to the recording unit of the record information, on thebasis of the correspondence information recorded on the recordingmedium.

By such construction, even in the recording apparatus which does nothave the correspondence information, it is possible to convert thetolerance length to the recording unit of the record information,relatively easily, by referring to the correspondence informationrecorded on the recording medium.

In another aspect of the first recording apparatus of the presentinvention, if the record information is recorded in the second area, thecontrolling device controls the recording device to record thepre-information in advance, into an area portion as being one portion ofthe first area, at least other than an area portion having a sizecorresponding to the tolerance length, with a position of the firstrecording layer corresponding to an edge on the inner circumferentialside of an area portion in the second area in which the recordinformation is unrecorded as a starting point.

According to this aspect, if the record information is already recordedin the second area, the area portion of the first area in which thepre-information can be pre-recorded increases. Therefore, it is possibleto further reduce a time length required for the finalizing.

In another aspect of the first recording apparatus of the presentinvention, if the record information is newly recorded into the secondarea, the controlling device controls the recording device to record thepre-information in advance, into an area portion as being one portion ofthe first area having a size of an area portion in the second area inwhich the record information is newly recorded, following the areaportion in which the pre-recorded information is recorded in advance.

According to this aspect, if the record information is newly recordedinto the second area, it is possible to pre-record the pre-informationinto an area portion of the first area having a size of the newlyrecorded area portion (or the newly recorded record information).Therefore, it is possible to further reduce a time length required forthe finalizing.

In another aspect of the first recording apparatus of the presentinvention, the controlling device controls the recording device torecord the pre-information in advance, except an area portion in thefirst area in which the pre-information is recorded in advance.

According to this aspect, the area portion in which the pre-informationis pre-recorded is not redundantly overwritten with the pre-information.Therefore, there is no need to perform unnecessary pre-recording, sothat it is possible to perform efficient pre-recording. Moreover, thereis an advantage that the content of the efficient pre-information is notdamaged by the overwriting.

In another aspect of the first recording apparatus of the presentinvention, the record information is recorded into the first recordinglayer in one direction, and the record information is recorded into thesecond recording layer in another direction different from the onedirection.

According to this aspect, it is possible to receive the above-mentionedvarious benefits when the record information is recorded onto therecording medium in the opposite track path method.

In another aspect of the first recording apparatus of the presentinvention, the tolerance length is or is set to substantially 40 μm in aradial direction of the recording medium. Namely, the controlling devicecontrols the recording device to pre-record the pre-information as therecord information, into an area portion as being one portion of thefirst area, other than an area portion having a size of 40 μm in aradial direction of the recording medium, which is equivalent to thearea portion having a size corresponding to the tolerance length.

According to this aspect, in the case of a DVD-R, which is one standardof the recording medium, for example, the acceptable range of theposition shift in each recording layer is defined to be from −20 μm to20 μm. In other words, a relative position shift of −40 μm to 40 μm isallowed between the first recording layer and the second recordinglayer. Therefore, by performing the pre-recording on the basis of thetolerance length in view of the acceptable range, it is possible topreferably receive the above-mentioned various benefits. Of course, if adifferent value is determined as the acceptable range of the positionshift in another standard, it is preferable to use the value instead of40 μm.

In another aspect of the first recording apparatus of the presentinvention, the clearance length is or is set to substantially 84 μm.Namely, the sum of (i) the spot radius of the laser light on the firstrecording layer if the laser light is focused on the second recordinglayer and (ii) the relative eccentric shift of the first and secondrecording layers or the acceptable range of the eccentric shift issubstantially 84 μm.

According to this aspect, in the case of the DVD-R or the like, which isone standard of the recording medium, for example, it is possible topreferably perform the pre-recording in view of the clearance.

The above object of the present invention can be also achieved by asecond recording apparatus provided with: a recording device forrecording record information by irradiating laser light onto a recordingmedium provided with: (i) a first recording layer which is irradiatedwith the laser light to thereby record therein the record informationand which has a first area in which the record information is recorded;and (ii) a second recording layer which is irradiated with the laserlight through the first recording layer to thereby record therein therecord information and which has a second area in which the recordedinformation is recorded by irradiating the second area with the laserlight through an area portion of the first recording layer in which therecord information is unrecorded; and a controlling device forcontrolling the recording device to record pre-information in advance asthe record information, into an area portion as being one portion of thefirst area, at least other than an area portion having a sizecorresponding to a tolerance length, which indicates an acceptable rangeof a relative position shift between an address which is defined on thepredetermined position in the first recording layer and an address whichis related to the predetermined position in the second recording layer,with a position of the first recording layer corresponding to at leastone of an edge on an inner circumferential side and an edge on an outercircumferential side of an area portion in the second area in which therecord information is unrecorded as a starting point.

According to the second recording apparatus of the present invention, asin the first recording apparatus, by the operation of the recordingdevice, it is possible to record the record information onto therecording medium. Moreover, by the operation of the controlling device,the pre-information is recorded into an area portion as being oneportion of the first area, before the finalizing.

Particularly in the second recording apparatus, the pre-information ispre-recorded into an area portion as being one portion of the firstarea, at least other than an area portion having a size corresponding tothe tolerance length, from a position of the first recording layercorresponding to at least one of the edge on the inner circumferentialside and the edge on the outer circumferential side of an area portionin the second area in which the record information is unrecorded. Inother words, even if the edge on the outer circumferential side of thefirst area does not correspond to the edge on the inner circumferentialside of the second area, it is possible to receive the same benefits asthose owned by the first recording apparatus.

Therefore, according to the second recording apparatus of the presentinvention, as in the above-mentioned first recording apparatus, it ispossible to preferably perform the pre-recording in order to reduce atime length required for the finalizing, even on the informationrecording medium having a plurality of recording layers.

Incidentally, in response to the various aspects of the above-mentionedfirst recording apparatus of the present invention, the second recordingapparatus of the present invention can adopt various aspects.

(Recording Method)

The above object of the present invention can be also achieved by afirst recording method in a recording apparatus provided with: arecording device for recording record information by irradiating laserlight onto a recording medium provided with: (i) a first recording layerwhich is irradiated with the laser light to thereby record therein therecord information and which has a first area in which the recordinformation is recorded; and (ii) a second recording layer which isirradiated with the laser light through the first recording layer tothereby record therein the record information and which has a secondarea whose edge on an inner circumferential side corresponds to an edgeon an outer circumferential side of the first area, the recording methodprovided with: a first controlling process of controlling the recordingdevice to record the record information; and a second controllingprocess of controlling the recording device to record pre-information inadvance as the record information, into an area portion as being oneportion of the first area, at least other than an area portion having asize corresponding to a tolerance length, which indicates an acceptablerange of a relative position shift between an address which is definedon the predetermined position in the first recording layer and anaddress which is related to the predetermined position in the secondrecording layer, with the edge on the outer circumferential side of thefirst area as a starting point.

According to the first recording method of the present invention, it ispossible to receive the same benefits as those owned by theabove-mentioned first recording apparatus of the present invention.

Incidentally, in response to the various aspects of the above-mentionedfirst recording apparatus of the present invention, the first recordingmethod of the present invention can adopt various aspects.

The above object of the present invention can be also achieved by asecond recording method in a recording apparatus provided with: arecording device for recording record information by irradiating laserlight onto a recording medium provided with: (i) a first recording layerwhich is irradiated with the laser light to thereby record therein therecord information and which has a first area in which the recordinformation is recorded; and (ii) a second recording layer which isirradiated with the laser light through the first recording layer tothereby record therein the record information and which has a secondarea in which the recorded information is recorded by irradiating thesecond area with the laser light through an area portion of the firstrecording layer in which the record information is unrecorded, therecording method provided with: a first controlling process ofcontrolling the recording device to record the record information; and asecond controlling process of controlling the recording device to recordpre-information in advance as the record information, into an areaportion as being one portion of the first area, at least other than anarea portion having a size corresponding to a tolerance length, whichindicates an acceptable range of a relative position shift between anaddress which is defined on the predetermined position in the firstrecording layer and an address which is related to the predeterminedposition in the second recording layer, with a position of the firstrecording layer corresponding to at least one of an edge on an innercircumferential side and an edge on an outer circumferential side of anarea portion in the second area in which the record information isunrecorded as a starting point.

According to the second recording method of the present invention, it ispossible to receive the same benefits as those owned by theabove-mentioned second recording apparatus of the present invention.

Incidentally, in response to the various aspects of the above-mentionedsecond recording apparatus of the present invention, the secondrecording method of the present invention can adopt various aspects.

(Computer Program)

The above object of the present invention can be also achieved by acomputer program of instructions for recording control and for tangiblyembodying a program of instructions executable by a computer provided inthe first or second recording apparatus (including its various aspects),to make the computer function as at least one portion of the recordingapparatus (specifically, e.g. the controlling device).

According to the computer program of the present invention, theabove-mentioned first or second recording apparatus of the presentinvention can be relatively easily realized as a computer reads andexecutes the computer program from a program storage device, such as aROM, a CD-ROM, a DVD-ROM, and a hard disk, or as it executes thecomputer program after downloading the program through a communicationdevice.

Incidentally, in response to the various aspects of the above-mentionedfirst or second recording apparatus of the present invention, thecomputer program of the present invention can adopt various aspects.

The above object of the present invention can be also achieved by acomputer program product in a computer-readable medium for tangiblyembodying a program of instructions executable by a computer provided inthe above-mentioned first or second recording apparatus of the presentinvention (including its various aspects), to make the computer functionas at least one portion of the recording apparatus (specifically, e.g.the controlling device).

According to the computer program product of the present invention, theabove-mentioned first or second recording apparatus can be embodiedrelatively readily, by loading the computer program product from arecording medium for storing the computer program product, such as a ROM(Read Only Memory), a CD-ROM (Compact Disc—Read Only Memory), a DVD-ROM(DVD Read Only Memory), a hard disk or the like, into the computer, orby downloading the computer program product, which may be a carrierwave, into the computer via a communication device. More specifically,the computer program product may include computer readable codes tocause the computer (or may comprise computer readable instructions forcausing the computer) to function as the above-mentioned first or secondrecording apparatus.

These effects and other advantages of the present invention will becomemore apparent from the following embodiments.

As explained above, the first or second recording apparatus of thepresent invention is provided with the recording device and thecontrolling device. The first or second recording method of the presentinvention is provided with the first controlling process and the secondcontrolling process. Therefore, it is possible to preferably perform thepre-recording in order to reduce a time length required for thefinalizing, even on the information recording medium having a pluralityof recording layers.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 are a substantial plan view showing the basic structure of anoptical disc in an embodiment of the present invention, and a schematiccross sectional view of the optical disc and a corresponding conceptualdiagram showing a recording area structure in the radial direction.

FIG. 2 is a block diagram conceptually showing the basic structure of arecording/reproducing apparatus in the embodiment.

FIG. 3 is a flowchart conceptually showing a flow of a pre-recordingoperation into a middle area, out of the recording operation of therecording/reproducing apparatus in the embodiment.

FIG. 4 are schematic conceptual views conceptually showing a positiontolerance.

FIG. 5 are schematic conceptual views conceptually showing an eccentricclearance out of clearance.

FIG. 6 are schematic conceptual views conceptually showing a spotclearance out of clearance.

FIG. 7 is a graph conceptually showing a specific example of acorresponding equation.

FIG. 8 is a schematic conceptual view schematically showing arelationship between each area and an address on the optical disc whendummy data or the like is pre-recorded into the middle area.

FIG. 9 is a schematic conceptual view schematically showing therelationship between each area and the address on the optical disc ifthe dummy data or the like is already pre-recorded in the middle area.

FIG. 10 is a schematic conceptual view showing the specific value of theaddress of a DVD-R with a diameter of 12 cm, which is one specificexample of the optical disc.

FIG. 11 is a schematic conceptual view showing the specific value of theaddress of a DVD-R with a diameter of 8 cm, which is another specificexample of the optical disc.

FIG. 12 is a flowchart conceptually showing a flow of a first modifiedoperation example.

FIG. 13 is a schematic conceptual view schematically showing therelationship between each area and the address on the optical disc whenthe dummy data or the like is pre-recorded into the middle area in thecase where an ODTA is used.

FIG. 14 is a schematic conceptual view schematically showing therelationship between each area and the address on the optical disc ifthe dummy data or the like is already pre-recorded in the middle area inthe case where the ODTA is used.

FIG. 15 is a flowchart conceptually showing a flow of a second modifiedoperation example.

FIG. 16 is a schematic conceptual view schematically showing therelationship between each area and the address on the optical disc whenthe dummy data or the like is pre-recorded into the middle area in thecase where an ODTA is newly used;

DESCRIPTION OF REFERENCE CODES

-   100 Optical disc-   109, 119 Middle area-   104, 114 ODTA-   200 Recording/reproducing apparatus-   352 Optical pickup-   353 Signal recording/reproducing device-   354, 359 CPU-   355, 360 Memory

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the best mode for carrying out the invention will beexplained in each embodiment in order, with reference to the drawings.

At first, with reference to FIG. 1, an explanation will be given to anoptical disc on which data is recorded and reproduced by arecording/reproducing apparatus 200 (refer to FIG. 2) as being anembodiment according to the recording apparatus of the presentinvention. FIG. 1(a) is a substantial plan view showing the basicstructure of an optical disc in the embodiment, and FIG. 1(b) is aschematic cross sectional view of the optical disc and a correspondingconceptual diagram showing a recording area structure in the radialdirection.

As shown in FIG. 1(a) and FIG. 1(b), an optical disc 100 has a recordingsurface on a disc main body with a diameter of about 12 cm, as is a DVD.On the recording surface, the optical disc 100 is provided with: acenter hole 101 as being the center; a lead-in area 102 or a lead-outarea 118; data areas 105 and 115; and middle areas 109 and 119. At thistime, the middle area 109 constitutes one specific example of the “firstarea” of the present invention. Then, in the optical disc 100, recordinglayers or the like are laminated on a transparent substrate 110, forexample. In each recording area of the recording layers, a track ortracks, such as groove tracks and land tracks, are alternately placed,spirally or concentrically, with the center hole 101 as the center.Moreover, on the track, data is divided by a unit of ECC block andrecorded. The ECC block is a data management unit by which the recordinginformation can be error-corrected.

Incidentally, the present invention is not particularly limited to theoptical disc having the three areas as described above. For example,even if the lead-in area 102, the lead-out area 118 or the middle area109 (119) do not exist, a data structure and the like explained belowcan be constructed. Moreover, as described later, the lead-in area 102and the lead-out area 118 or the middle area 109 (119) may be furthersegmentized.

Particularly, the optical disc 100 in the embodiment, as shown in FIG.1(b), has such a structure that an L0 layer and an L1 layer, whichconstitute one example of the “first and second recording layers” of thepresent invention, respectively, are laminated on the transparentsubstrate 110. Upon the recording and reproduction of such a dual-layertype optical disc 100, the data recording/reproduction in the L0 layeror the L1 layer is performed, depending on which recording layer has thefocus position of laser light LB, irradiated from the lower side to theupper side in FIG. 1(b). In particular, in the L0 layer, the data isrecorded from the inner to the outer circumferential side, while in theL1 layer, the data is recorded from the outer to the innercircumferential side. In other words, the optical disc 100 in theembodiment corresponds to an optical disc in the opposite track pathmethod. Even an optical disc in a parallel track path method can alsoreceive various benefits described later, by adopting a structurediscussed below.

The optical disc 100 in the embodiment is provided with RMA (RecordingManagement Areas) 103 and 113 on the inner circumferential side of thelead-in area 102 and the lead-out area 118, and ODTA (Outer Disc TestingAreas) 104 and 114 on the outer circumferential side of the middle areas109 and 119.

The RMA 103 and 113 are recording areas to record therein variousmanagement information for managing the recording of the data onto theoptical disc 100. Specifically, the management information or the likewhich indicates the arrangement or the recording state or the like ofthe data recorded on the optical disc 100, for example, is recorded.

The ODTA 104 and 114 are recording areas to perform an OPC (OptimumPower Control) process of adjusting (or calibrating) the laser power oflaser light LB, in recording the data onto the optical disc 100. An OPCpattern is recorded into the ODTA 104 and 114 while the laser power ischanged in stages and the reproduction quality (e.g. asymmetry, etc.) ofthe recorded OPC pattern is measured, by which an optimum laser power inrecording the data is calculated. In particular, the ODTA 114 of the L1layer, which constitutes one specific example of the “second area” ofthe present invention, is located adjacent to the middle area 119, andthe ODTA 114 of the L1 layer is located not to overlap the ODTA 104 ofthe L0 layer and the middle area 109, as viewed from the irradiationside of the laser light LB. In order to preferably perform the OPCprocess without influence of the other recording layer, when the OPCprocess is performed by using the ODTA 114 of the L1 layer, the OPCpattern is recorded through the L0 layer in which the data isunrecorded. Obviously, the same is true for the ODTA 104 of the L0layer.

Moreover, the optical disc 100 in the embodiment is not limited to adual-layer, single-sided type, but may be a dual layer, double-sidedtype. Furthermore, the optical disc 100 in the embodiment is not limitedto the optical disc having the two recording layers, as described above,but may be an optical disc of a multilayer type which has three or morelayers.

(Recording/Reproducing Apparatus)

Next, with reference to FIG. 2 to FIG. 16, the structure and operationof the recording/reproducing apparatus 200, as being an embodimentaccording to the recording apparatus of the present invention, will beexplained.

(1) Basic Structure

At first, with reference to FIG. 2, the basic structure of therecording/reproducing apparatus 200 will be discussed. FIG. 2 is a blockdiagram conceptually showing the basic structure of therecording/reproducing apparatus 200 in the embodiment. Incidentally, therecording/reproducing apparatus 200 has a function of recording the dataonto the optical disc 100 and a function of reproducing the datarecorded on the optical disc 100.

As shown in FIG. 2, the recording/reproducing apparatus 200 is providedwith: a disc drive 300 into which the optical disc 100 is actuallyloaded and in which the data is recorded and reproduced; and a hostcomputer 400, such as a personal computer, for controlling the recordingand reproduction of the data with respect to the disc drive 300.

The disc drive 300 is provided with: the optical disc 100; a spindlemotor 351; an optical pickup 352; a signal recording/reproducing device353; the CPU (drive control device) 354; a memory 355; a datainput/output control device 306; and a bus 357. Moreover, the hostcomputer 400 is provided with: a CPU 359; a memory 360; anoperation/display control device 307; an operation button 310; a displaypanel 311; and a data input/output control device 308.

The spindle motor 351 is intended to rotate and stop the optical disc100, and operates upon accessing the optical disc. More specifically,the spindle motor 351 is constructed to rotate and stop the optical disc100 at a predetermined speed, under spindle servo from a not-illustratedservo unit or the like.

The optical pickup 352 constitutes one specific example of the“recording device” of the present invention and is provided with asemiconductor laser device, a lens, and the like, to perform therecording/reproduction with respect to the optical disc 100. Morespecifically, the optical pickup 352 irradiates the optical disc 100with a light beam, such as a laser beam, as reading light with a firstpower upon reproduction, and as writing light with a second power uponrecording, with it modulated.

The signal recording/reproducing device 353 controls the spindle motor351 and the optical pickup 352, to thereby perform therecording/reproduction with respect to the optical disc 100. Morespecifically, the signal recording/reproducing device 353 is providedwith: a laser diode (LD) driver; a head amplifier; and the like, forexample. The laser diode driver (LD driver) drives a not-illustratedsemiconductor laser device located in the optical pickup 352. The headamplifier amplifies the output signal of the optical pickup 352, i.e.the reflective light of a light beam, and outputs the amplified signal.More specifically, the signal recording/reproducing device 353 drivesthe not-illustrated semiconductor laser device located in the opticalpickup 352, in order to determine an optimum laser power by therecording and reproduction processes for the OPC pattern, together witha not-illustrated timing generator or the like, under the CPU 354, uponthe OPC process.

The memory 355 is used in the whole data processing and the OPC processor the like on the disc drive 300, including a buffer area for therecord/reproduction data, an area used as an intermediate buffer whendata is converted into the data that can be used on the signalrecording/reproducing device 353, and the like. Moreover, the memory 355is provided with: a ROM area into which a program for performing anoperation as a recording device, i.e. firmware, is stored; a buffer fortemporary storage of the record/reproduction data; a RAM area into whicha parameter required for the operation of a firmware program or the likeis stored; and the like.

The CPU (drive control device) 354 is connected to thesignal-recording/reproducing device 353 and the memory 355 through thebus 357, and controls the entire disc drive 300 by giving an instructionto various controlling devices. Normally, software or firmware foroperating the CPU 354 is stored in the memory 355.

The data input/output control device 306 controls the input/output ofthe data from the exterior with respect to the disc drive 300, tothereby perform storage to and export from the data buffer on the memory355. A drive control command issued from the external host computer 400connected to the disc drive 300 through an interface, such as a SCSI andan ATAPI, is transmitted to the CPU 354 through the data input/outputcontrol device 306. Moreover, the record/reproduction data is alsotransmitted to and received from the host computer 400 through the datainput/output control device 306, in the same manner.

The operation/display control device 307 receives an operationinstruction and performs display with respect to the host computer 400,and transmits an instruction by the operation button 310, such as aninstruction to record or reproduce, to the CPU 359. The CPU 359 maytransmit a control command to the disc drive 300, through the datainput/output control device 308, on the basis of instruction informationfrom the operation/display control device 307, to thereby control theentire disc drive 300. In the same manner, the CPU 359 can transmit acommand for requesting the disc drive 300 to transmit an operationalstate to the host, with respect to the disc drive 300. By this, theoperational state of the disc drive 300, such as during recording andduring reproduction, can be recognized, so that the CPU 359 can outputthe operational state of the disc drive 300 to the display panel 310,such as a fluorescent tube and an LCD, through the operation/displaycontrol device 307.

The memory 360 is an inner storage apparatus used by the host computer400, and is provided with: a ROM area into which a firmware program,such as a BIOS (Basic Input/Output System), is stored; a RAM area intowhich a parameter required for the operation of an operating system andan application program or the like is stored; and the like. Moreover,the memory 360 may be connected to a not-illustrated external storageapparatus, such as a hard disk, through the data input/output controldevice 308.

One specific example used by combining the disc drive 300 and the hostcomputer 400, as explained above, is household equipment, such asrecorder equipment for recording and reproducing video images. Therecorder equipment records a video signal from a broadcast receptiontuner and an external connection terminal, onto a disc, and outputs thevideo signal reproduced from the disc to external display equipment,such as a television. The operation as the recorder equipment isperformed by executing a program stored in the memory 360, on the CPU359. Moreover, in another specific example, the disc drive 300 is a discdrive (hereinafter referred to as a “drive”, as occasion demands), andthe host computer 400 is a personal computer and a work station. Thehost computer, such as the personal computer, and the drive areconnected through the data input/output control devices 306 and 308,such as the SCSI and the ATAPI, and application, such as writingsoftware, installed in the host computer 400 controls the disc drive300.

(2) Operation Principle

Next, with reference to FIG. 3 to FIG. 11, the recording operation ofthe recording/reproducing apparatus 200 in the embodiment will bediscussed. Here, the overall outline of the operation principle will beexplained by using FIG. 3, and supplementary or more detailedexplanation will be given by using FIG. 4 to FIG. 11. FIG. 3 is aflowchart conceptually showing a flow of a pre-recording operation intothe middle areas 109 and 119, out of the recording operation of therecording/reproducing apparatus 200 in the embodiment.

The recording/reproducing apparatus 200 records movie data, audio data,data for PC or the like into the data areas 105 and 115. At this time,as a general rule, it records the data into the data area 115 of the L1layer after recording the data into the data area 105 of the L0 layer.In other words, the recording/reproducing apparatus 200 records the datainto the data area 115 of the L1 layer, by irradiating the L1 layer withthe laser light LB through the data area 105 of the L0 layer in whichthe data is already recorded. The same is true for other recordingareas, as a general rule. At this time, the recording/reproducingapparatus 200 pre-records dummy data (e.g. “00h” data, etc.) into themiddle areas 109 and 119, as occasion demands, if needed. Thepre-recording will be discussed below.

As shown in FIG. 3, under the control of the CPU 354 or 359, whichconstitutes one specific example of the “controlling device” of thepresent invention, at first, the position tolerance of each of the L0layer and the L1 layer is obtained (step S101). Instead of obtaining theposition tolerance, the acceptable value of the position tolerance inthe standard may be obtained as the position tolerance. The positiontolerance is a value of a position shift between a position where apredetermined address in design is to be originally disposed and aposition where the predetermined address is actually disposed on theoptical disc 100 or an acceptable range of the position shift. Now, theposition tolerance will be explained in more detail, with reference toFIG. 4. FIG. 4 are schematic conceptual views conceptually showing theposition tolerance.

As shown in FIG. 4(a), it is assumed that an address “X” is defined at aradial position “r” in design. By this, the arrangement of the lead-inarea 101, the data areas 105 and 115, the lead-out area 118, and themiddle areas 109 and 119 is defined, in design. At this time, there islikely a case where the address “X” is not accurately defined at theradial position “r” where the address “X” is to be originally defined,due to manufacturing errors of a stampa or the like, which is to form aland pre-pit or wobble which defines the address; in other words, due tomanufacturing errors of an original disc for producing the stampa,errors in the radial position of a cutting machine for producing theoriginal disc, uneven track pitches, or the like. Alternatively, thereis likely a case where the address “X” is not accurately defined at theradial position “r” where the address “X” is to be originally defined,due to an individual difference by heat contraction or the like in theproduction of the optical disc 100.

Specifically, as shown in FIG. 4(b), it is likely that an address “X+ΔX”is defined at the radial position “r” where the address “X” is to beoriginally defined. At this time, the address “X” is defined at a radialposition “r-Δr1” obtained by shifting from the radial position “r” tothe inner circumferential side by “Δr1”. A value of “Δr1” or theacceptable range of “Δr1” is referred to the position tolerance. Theposition tolerance is likely caused in each recording layer, so that inthe step S101 in FIG. 3, the position tolerance is obtained in both theL0 layer and the L1 layer. Incidentally, if the state of FIG. 4(b)indicates the state that the position tolerance is caused, FIG. 4(a) isa view which indicates the state that position tolerance is “0”.

In FIG. 3 again, a layer tolerance, which constitutes one specificexample of the “tolerance length” of the present invention, iscalculated, by adding the position tolerance in the L0 layer to theposition tolerance in the L1 layer, obtained in the step S101, under thecontrol of the CPU 354 or 359 (step S102). Namely, the layer toleranceindicates the acceptable range of a relative position shift (or therelative position shift itself) between (i) the address which is definedon a predetermined radial position in the L0 layer and (ii) the addresswhich is related to the predetermined radial position in the L1 layer(i.e. the address which is defined on the predetermined radial positionin the L1 layer).

Then, a clearance is calculated (step S103). Specifically, a clearancerelated to an eccentricity corresponding to a shift of the centerpositions or the like of the L0 layer and the L1 layer (hereinafterreferred to as an “eccentric clearance”, as occasion demands) and aclearance related to the size of a beam spot of the defocused laserlight (hereinafter referred to as a “spot clearance”, as occasiondemands) are calculated and added. Now, the clearance will be discussedwith reference to FIG. 5 and FIG. 6. FIG. 5 are schematic conceptualviews conceptually showing the eccentric clearance out of the clearance.FIG. 6 are schematic conceptual views conceptually showing the spotclearance out of the clearance.

As shown in FIG. 5(a), in the case of the optical disc 100 without aneccentricity, the address “X” defined at the radial position “r” in theL0 layer and an address “Y” defined at the radial position “r” in the L1layer are in such a relationship that they face (or are opposed) to eachother on the track of the radius “r”. Incidentally, the eccentricity isa relative shift of the L0 layer and the L1 layer, caused by a shift ofthe center positions of the both layers, a position shift of the centerpositions in pasting the L0 layer and the L1 layer, or the like.

On the other hand, as shown in FIG. 5(b), in the case of the opticaldisc 100 with an eccentricity, the address “X” defined at the radialposition “r” in the L0 layer and the address “Y” defined at the radialposition “r” in the L1 layer face only at two points on the track of theradius “r”. In other words, the address “X” of the L0 layer and theaddress “Y” of the L1 layer, which are to be originally defined at thefacing positions, do not face in most places. Specifically, the sum ofthe eccentricity in the L0 layer and the L1 layer corresponds to theeccentric clearance. In the case of FIG. 5(b), the address “X” of the L0layer is located away from the address “Y” of the L1 layer, on the outercircumferential side, by “Δr2” corresponding to the amount of theeccentricity. The maximum value of “Δr2” corresponds to the eccentricclearance.

Moreover, as shown in FIG. 6(a), if the laser light LB is focused on theL1 layer, a beam spot with a predetermined radius of “Δr3” is formed onthe L0 layer. Now, as described above, a case where the data is recordedinto the L1 layer by irradiating the L1 layer with the laser light LBthrough the L0 layer in which the data is recorded, is considered. Asshown in FIG. 6(a), in the case where the data is recorded until theaddress “X” of the L0 layer, if the laser light LB is focused on theaddress “Y” of the L1 layer which faces the address “X”, the L1 layer isirradiated with the left half of the laser light LB through the L0 layerin which the data is recorded, while the L1 layer is irradiated with theright half of the laser light LB through the L0 layer in which the datais unrecorded. Therefore, only by recording the data into the L1 layerwhich faces the L0 layer in which the data is recorded withoutconsidering the above case, it is impossible to preferably record thedata into the L1 layer by irradiating the L1 layer with the laser lightLB through the L0 layer in which the data is recorded

Thus, as shown in FIG. 6(b), it is necessary to shift the focus positionof the laser light LB in the case where the data is recorded into the L1layer, to the inner circumferential side, by a distance corresponding tothe radius “Δr3” of the beam spot, from the position represented by theaddress “Y” of the L1 layer which faces the address “X” of the L0 layerin which the data is recorded. Specifically, it is necessary to focusthe laser light LB on a position represented by an address “Y−ΔX”obtained by shifting to the inner circumferential side by a variable“ΔX” of the address corresponding to the radius “Δr3” of the beam spot.The maximum value of the radius “Δr3” of the beam spot corresponds tothe spot clearance.

In the step S103 in FIG. 3, the clearance is calculated by adding theeccentric clearance, explained in FIG. 5, to the spot clearance,explained in FIG. 6.

In FIG. 3 again, under the control of the CPU 354 or 359, the totalamount (sum) “L” of the layer tolerance calculated in the step S102 andthe clearance calculated in the step S103 is calculated (step S104).Then, under the control of the CPU 354 or 359, a most outercircumferential address (i.e. an address “C” in the edge portion on theouter circumferential side) “C” of the middle area 109 in the L0 layeris calculated (step S105). Then, under the control of the CPU 354 or359, an address located on position which is shifted by the distance “L”toward the inner circumferential side from the position represented bythe address “C” is calculated as an address “B” where the pre-recordingis ended, on the basis of a corresponding equation (step S106). At thistime, the most outer circumferential position of the middle area 109 anda most inner circumferential position (i.e. an edge portion on the innercircumferential side) of the ODTA 114 have a correspondence relationship(i.e. they are defined at facing positions in design), so that, in otherwords, an address located on the position which is shifted by thedistance “L” toward the inner circumferential side from a position ofthe L0 layer corresponding to the most inner circumferential position ofthe ODTA 114 is calculated as the address “B”. The correspondingequation used in the step S106 indicates a correspondence relationshipbetween the size of the recording area (e.g. distance in the radialdirection) and the size of the data recorded in the recording area (e.g.the number of ECC blocks). The corresponding equation will be discussedin detail with reference to FIG. 7. FIG. 7 is a graph conceptuallyshowing a specific example of the corresponding equation.

As shown in FIG. 7, the corresponding equation is shown by a graph (orfunction), wherein the distance “L” in the radial direction is assignedto the horizontal axis and the number of ECC blocks is assigned to thevertical axis. At this time, a plurality of graphs depending on the typeof the optical disc 100 may be defined as the corresponding equation.For example, as shown in FIG. 7, in accordance with the size of theoptical disc 100, the corresponding equation (for example, the number ofECC blocks=5.442×L) of an optical disc with a diameter of 12 cm and thecorresponding equation (for example, the number of ECC blocks=3.5687×L)of an optical disc with a diameter of 8 cm may be defined. From thegraph, it is possible to obtain the size of the data which can berecorded into the recording area with the distance in the radialdirection of “L”. For example, if “L=124 μm”, the data with a size of675ECC blocks can be recorded in the optical disc with a diameter of 12cm, and the data with a size of 443ECC blocks can be recorded in theoptical disc with a diameter of 8 cm.

Incidentally, the corresponding equation may be stored in advance in thememory 355 or 360 in the recording/reproducing apparatus 200, whichconstitutes one specific example of the “storing device” of the presentinvention, or may be recorded on the optical disc 100. Moreover, it isobvious that the corresponding equation is not limited to the aspectshown in FIG. 7. For example, it may be a predetermined table. In short,information for defining a relationship between the distance in theradial direction and the size of the data which can be recorded in thedistance can be used as the above-mentioned corresponding equation.

The size of the data which can be recorded in the recording area withthe distance in the radial direction of “L”, which is obtained by usingthe corresponding equation of FIG. 7, is used in calculating the addressB. This is because the recording/reproducing apparatus 200 cannot easilycalculate the address “B” even if “L” is merely obtained as the distancein the radial direction. That is because the recording/reproducingapparatus 200 has difficulty in recognizing the position of therecording area in the L0 layer and the L1 layer by the “distance in theradial direction” and recognizes it by the address position. At thistime, the data in a predetermined size is recorded in a predeterminedaddress range, so that it is enough to make the recording/reproducingapparatus 200 recognize the distance in the radial direction of “L”, asthe size of the data. If the recording/reproducing apparatus 200recognizes the distance in the radial direction of “L”, as the size ofthe data which can be recorded in the recording area with the distance“L” in the radial direction, it is possible to relatively easilycalculate the address “B” by shifting to the inner circumferential sideby the address corresponding to the size, from the position of theaddress “C”.

In FIG. 3 again, after that, RMD (Recording Management Data) recorded inthe RMA 103 or 113 is obtained (step S107). The RMD includes informationwhich indicates the recording state of the data on the optical disc 100(i.e. which recording area has the data recorded, or which recordingarea does not have the data recorded).

Then, under the control of the CPU 354 or 359, it is judged whether ornot the dummy data or the like is already pre-recorded in the middlearea 109 of the L0 layer (step S108). This judgment is performed on thebasis of the RMD obtained in the step S107.

As a result of the judgment, if it is judged that the dummy data or thelike is not pre-recorded in the middle area 109 of the L0 layer (thestep S108: No), an address next to the most outer circumferentialaddress value of the data area 105 which is assigned to a land pre-pitor the like (i.e. the most inner circumferential address of the middlearea 109) is obtained as an address “A” where the pre-recording isstarted, under the control of the CPU 354 or 359 (step S109). On theother hand, if it is judged that the dummy data or the like ispre-recorded in the middle area 109 of the L0 layer (the step S108:Yes), an address value next to the most outer circumferential address ofthe pre-recorded dummy data or the like (i.e. the most outercircumferential address of the recording area in which the dummy data orthe like is pre-recorded, out of the middle area 109) is obtained as theaddress “A”, on the basis of the RMD obtained in the step S107, underthe control of the CPU 354 or 359 (step S110).

Then, under the control of the CPU 354 or 359, it is judged whether ornot the address “B” calculated in the step S106 is located on the outercircumferential side of the address “A” obtained in the step S109 or thestep S110 (step S111).

As a result, if it is judged that the address “B” is located on theouter circumferential side of the address “A” (the step S111: Yes),predetermined dummy data or the like is pre-recorded into the recordingarea from the address “A” to the address “B” out of the middle area 109of the L0 layer, under the control of the CPU 354 or 359 (step S112). Onthe other hand, if it is judged that the address “B” is not located onthe outer circumferential side of the address “A” (the step S111: No),the dummy data or the like is not pre-recorded into the middle area 109of the L0 layer, under the control of the CPU 354 or 359.

The aspect on the optical disc 100 at this time will be explained withreference to FIG. 8 and FIG. 9. FIG. 8 is a schematic conceptual viewschematically showing a relationship between each area and the addresson the optical disc 100 when the dummy data or the like is pre-recordedinto the middle area 109. FIG. 9 is a schematic conceptual viewschematically showing the relationship between each area and the addresson the optical disc 100 if the dummy data or the like is alreadypre-recorded in the middle area 109.

As shown in FIG. 8, if the dummy data is not pre-recorded in advance inthe middle area 109, the most inner circumferential address of themiddle area 109 in the L0 layer corresponds to the address “A”, the mostouter circumferential address of the middle area 109 in the L0 layercorresponds to the address “C”, and the address of the position obtainedby shifting to the inner circumferential side by the distance “L” fromthe edge portion on the outer circumferential side of the middle area109 in the L0 layer corresponds to the address “B”. Then, under thecontrol of the CPU 354 or 359, the dummy data is pre-recorded into therecording area from the address “A” to the address “B”, out of themiddle area 109. At this time, as shown in FIG. 8, it is possible torecord the OPC pattern into the ODTA 114 of the L1 layer, by irradiatingthe L1 layer with the laser light LB through the L0 layer in which thedata is unrecorded. In other words, if the OPC pattern is recorded intothe ODTA 114 of the L1 layer, the laser light LB is not irradiatedthrough the layer in which the data is recorded. In particular, therecording area as one portion of the middle area 109 in which the dummydata or the like is recorded is determined, in view of the layertolerance and the clearance, as described above. Namely, after a marginis ensured in view of both the layer tolerance and the clearance, thedummy data or the like is recorded into the middle area 109. Thus, evenif there arises a relative position shift between the L0 layer and theL1 layer due to the occurrence of the eccentricity and the positiontolerance, it is possible to record the OPC pattern into the ODTA 114 ofthe L1 layer by irradiating the L1 layer with the laser light LB throughthe L0 layer in which the data is unrecorded, with or without the dummydata pre-recorded in the middle area 109.

Incidentally, FIG. 8 shows a case where there arise the eccentricity inwhich the center of the L0 layer is shifted to the outer circumferentialside, as compared to the center of the L1 layer, the position tolerancein which the middle area 109 of the L0 layer is shifted to the outercircumferential side, and the position tolerance in which the ODTA 114of the L1 layer is shifted to the inner circumferential side. In otherwords, it shows the worst case where the middle area 109 of the L0 layerand the ODTA 114 of the L1 layer are overlapped most. Even in the worstcase, if the dummy data or the like is pre-recorded into the middle area109 in view of the layer tolerance and the clearance, as describedabove, it is possible to record the OPC pattern into the ODTA 114 of theL1 layer by irradiating the L1 layer with the laser light LB through theL0 layer in which the data is unrecorded, as shown in FIG. 8.

Moreover, as shown in FIG. 9, if the dummy data or the like is alreadypre-recorded in one portion of the middle area 109, the address next tothe most outer circumferential address of the recording area in whichthe dummy data or the like is pre-recorded corresponds to the address“A”, the most outer circumferential address of the middle area 109 inthe L0 layer corresponds to the address “C”, and the address of theposition obtained by shifting to the inner circumferential side by thedistance “L” from the edge portion on the outer circumferential side ofthe middle area 109 in the L0 layer corresponds to the address “B”.Then, under the control of the CPU 354 or 359, the dummy data or thelike is pre-recorded into the recording area from the address “A” to theaddress “B” out of the middle area 109. Even in this case, as in thecase of FIG. 8, even if there arises a relative position shift betweenthe L0 layer and the L1 layer due to the occurrence of the eccentricityand the position tolerance, it is possible to record the OPC patterninto the ODTA 114 of the L1 layer by irradiating the L1 layer with thelaser light LB through the L0 layer in which the data is unrecorded,with or without the dummy data pre-recorded in the middle area 109.

If the specific value of the address is applied, it is like FIG. 10 andFIG. 11. FIG. 10 is a schematic conceptual view showing the specificvalue of the address of a DVD-R with a diameter of 12 cm, which is onespecific example of the optical disc 100. FIG. 11 is a schematicconceptual view showing the specific value of the address of a DVD-Rwith a diameter of 8 cm, which is another specific example of theoptical disc 100.

Incidentally, in FIG. 10 and FIG. 11, in accordance with “20 μm” asbeing the acceptable range of the position tolerance in the standard ineach recording layer, “40 μm” is used as a specific numerical value ofthe layer tolerance. Moreover, “84 μm” is used as a specific numericalvalue of the clearance. Namely, the explanation is made in the casewhere L=84+40=124 μm. Moreover, FIG. 10 and FIG. 11 show the case wherea decrement address method is adopted in which the address decreasestoward the outer circumferential side in the L0 layer and the addressdecreases toward the inner circumferential side in the L1 layer. Ofcourse, in the case of an increment address method in which the addressincreases toward the outer circumferential side in the L0 layer and theaddress increases toward the inner circumferential side in the L1 layer,the specific-value is different.

As shown in FIG. 10, in the case of the DVD-R with a diameter of 12 cm,the address “A” (i.e. the most inner circumferential address of themiddle area 109 in the L0 layer) is “FDD109h”, and the address “C” (i.e.the position of the L0 layer corresponding to the most innercircumferential position of the ODTA 114 in the L1 layer) is “FDCCCAh”.Then, it can be seen from the graph of FIG. 7 that the size of the datawhich can be recorded in the recording area with the distance L in theradial direction L=124 μm is 675 ECC blocks (=2A3hECC blocks).Therefore, the address “B” is “FDCCCAh”+“2A3h”=“FDCF6Dh”. For reference,the most inner circumferential address of the middle area 119 in the L1layer is “022EF6h”, and most inner circumferential address of the ODTA114 in the L1 layer is “023574h”.

Moreover, as shown in FIG. 11, in the case of the DVD-R with a diameterof 8 cm, the address “A” is “FF3030h”, and the address “C” is “FF2D67h”.Then, it can be seen from the graph of FIG. 7 that the size of the datawhich can be recorded in the recording area with the distance L in theradial direction of L=124 μm is 443 ECC blocks (=1BBhECC blocks).Therefore, the address “B” is “FF2D67h”+“1BBh”=“FF2F22h”. For reference,the most inner circumferential address of the middle area 119 in the L1layer is “00CFCFh”, and most inner circumferential address of the ODTA114 in the L1 layer is “00D4D7h”.

Incidentally, FIG. 10 and FIG. 11 show the case where the middle areas109 and 119 are disposed at positions determined in advance in thestandard. However, it is obvious that the middle areas 109 and 119 maybe constructed to be located on the further inner circumferential sideif the size of the data recorded in the data areas 105 and 115 is small.

As explained above, according to the recording/reproducing apparatus 200in the embodiment, the recording area as one portion of the middle area109 in which the dummy data or the like is recorded is determined,without influence on the recording of the OPC pattern into the ODTA 114,in view of the layer tolerance and the clearance. Thus, even if therearises a relative position shift between the L0 layer and the L1 layerdue to the occurrence of the eccentricity and the position tolerance, itis possible to record the OPC pattern into the ODTA 114 of the L1 layerby irradiating the L1 layer with the laser light LB through the L0 layerin which the data is unrecorded, with or without the dummy datapre-recorded in the middle area 109. Thus, it is possible to preferablyperform the OPC process by using the ODTA 114.

Moreover, since the dummy data or the like can be pre-recorded into themiddle area 109 before the finalizing, it is possible to reduce a timelength required for the finalizing. In summary, according to therecording/reproducing apparatus 200 in the embodiment, there is such agreat advantage which cannot be realized by an existingrecording/reproducing apparatus that although it can reduce a timelength required for the finalizing, it does not have an adverse effecton the OPC process performed by using the ODTA 114.

In addition, according to the recording/reproducing apparatus 200 in theembodiment, the address position (specifically, the address “B”) iscalculated by a data recording unit, on the basis of not the distance inthe radial direction of the optical disc 100 but the correspondingequation shown in FIG. 7. Thus, the above-mentioned pre-recording can beperformed in a format easily recognized or easily handled by therecording/reproducing apparatus 200. Therefore, it is possible to reducea processing load required for the recording operation of therecording/reproducing apparatus 200.

Moreover, by using the plurality of corresponding equations, it ispossible to determine the recording area as being one portion of themiddle area 109 in which the dummy data or the like can be pre-recorded,depending on the type of the optical disc 100 (e.g. depending on thesize of the diameter and a difference in the standard). Alternatively,it is possible to determine the recording area as being one portion ofthe middle area 109 in which the dummy data or the like can bepre-recorded, depending on where the middle area 109 is disposed (e.g.depending on whether the middle area 109 is located relatively on theinner circumferential side of the optical disc 100, or relatively on themiddle circumferential side, or relatively on the outer circumferentialside).

Incidentally, in the above-mentioned embodiment, the pre-recording inthe middle area 109 of the L0 layer is explained; however, this can beapplied to a case where the dummy data or the like is pre-recorded intothe lead-in area 102 or the like of the L0 layer. In other words, ifthere is a recording area in which the data needs to be recorded throughthe unrecorded L0 layer, in a recording area of the L1 layercorresponding to the lead-in area 102 or the like of the L0 layer (or arecording area adjacent to the corresponding L1 layer), it is possibleto determined the recording area as being one portion of the lead-inarea 102 or the like in which the dummy data or the like can bepre-recorded, as described above. Moreover, the same can be also appliedto the middle area 119 and the lead-out area 118 of the L1 layer.

FIRST MODIFIED OPERATION EXAMPLE

Next, with reference to FIG. 12, the first modified operation example ofthe recording/reproducing apparatus 200 in the embodiment will bediscussed. FIG. 12 is a flowchart conceptually showing a flow of thefirst modified operation example. Incidentally, the same constitutionalelements and the same processes as those in the operation, explainedwith reference to FIG. 3 to FIG. 10, carry the same reference numeralsand the same step numbers, and the explanation thereof are omitted, asoccasion demands.

The first modified operation example is an operation example in whichthe dummy data is pre-recorded into the middle area 109 if the OPCpattern or the like is already recorded in the ODTA 114 of the L1 layer.As shown in FIG. 12, the step S101 to the step S110 in FIG. 3 areperformed in the same manner even in the first modified operationexample.

Then, under the control of the CPU 354 or 359, it is judged whether ornot the ODTA 114 of the L1 layer (or one portion thereof) is alreadyused (i.e. whether or not the OPC pattern or the like is alreadyrecorded) (step S201).

As a result of the judgment, if it is judged that the ODTA 114 of the L1layer is already used (the step S201: Yes), a most outer circumferentialaddress “E” of the already-used ODTA 114 (i.e. a most outercircumferential address of the recording area in which the OPC patternor the like is recorded) is obtained, by referring to the RMD obtainedin the step S107, for example, under the control of the CPU 354 or 359(step S202). Then, a most outer circumferential address “D” of themiddle area 119 in the L1 layer, which is assigned to a land pre-pit orthe like or which is determined in advance in the standard, is obtained(step S203).

Then, from a difference of the address “D” and the address “E”, a size“M” of the data which can be recorded in the recording area between theaddress “D” and the address “E” is calculated (step S204). In otherwords, the size of the already-used recording area out of the ODTA 114in the L1 layer (or the size of the recorded OPC pattern) is calculated.For example, if the decrement address method is adopted, M=D−E. Then,from the address “B” calculated in the step S106, the address value of aposition obtained by shifting to the outer circumferential side by thedata size “M” is calculated as a new address “B” (step S205). Forexample, if the decrement address method is adopted, B=B−M. On the otherhand, if the increment address method is adopted, B=B+M. In other words,the address value of a position which is obtained by shifting to theinner circumferential side by “L” from the address of the position inthe L0 layer corresponding to the position of the L1 layer specified bythe address “E”, corresponds to the new address “B” calculated in thestep S205. Then, the step S111 and the step S112 in FIG. 3 areperformed, and the predetermined dummy data is pre-recorded into therecording area from the address “A” to the address “B” out of the middlearea 109 in the L0 layer.

On the other hand, if it is judged that the ODTA 114 of the L1 layer isnot used yet (i.e. unused) (the step S201: No), the step S111 and thestep S112 in FIG. 3 are performed without the above-mentioned step S202to step S205, and the predetermined dummy data is pre-recorded into therecording area from the address “A” to the address “B” out of the middlearea 109 in the L0 layer.

The aspect on the optical disc 100 at this time will be discussed withreference to FIG. 13 and FIG. 14. FIG. 13 is a schematic conceptual viewschematically showing the relationship between each area and the addresson the optical disc 100 when the dummy data or the like is pre-recordedin the middle area 109 in the case where the ODTA 114 is used. FIG. 14is a schematic conceptual view schematically showing the relationshipbetween each area and the address on the optical disc 100 if the dummydata or the like is already pre-recorded in the middle area 109 in thecase where the ODTA 114 is used.

As shown in FIG. 13, the most inner circumferential address of themiddle area 109 in the L0 layer corresponds to the address “A”, and themost outer circumferential address of the middle area 109 in the L0layer corresponds to the address “C”. Moreover, the address of theposition which is obtained by shifting to the inner circumferential sideby the distance “L” and to the outer circumferential side by the datasize “M” from the edge portion on the outer circumferential side of themiddle area 109 in the L0 layer corresponds to the address “B”. This isbecause if the recording area as being one portion of the ODTA 114 ofthe L1 layer is used, it is only necessary to record the OPC pattern orthe like by irradiating the laser light LB through the L0 layer in whichthe data is unrecorded, with respect to the recording area of the ODTA114 other than the one portion. In other words, that is because therecording of the OPC pattern into the not-used ODTA is not adverselyaffected even if the dummy data is recorded to the further outercircumferential side, since the recording area as being one portion ofthe ODTA 114 of the L1 layer is used. Then, under the control of the CPU354 or 359, the dummy data is pre-recorded into the recording area fromthe address “A” to the address “B”, out of the middle area 109.

Moreover, as shown in FIG. 14, even if the dummy data is pre-recorded inadvance in the middle area 109, it is obvious that the dummy data or thelike may be pre-recorded, in view of the size “M” of the recording areaof the ODTA 114 in the L1 layer, which is already used as describedabove.

As explained above, according to the first modified operation example,even if the ODTA 114 (or one portion thereof is already used, it ispossible to determined the recording area as being one portion of themiddle area 109 in which the dummy data can be pre-recorded before thefinalize process, without adverse effect on the OPC process performed byusing the ODTA 114. Therefore, it is possible to receive theabove-mentioned various benefits.

SECOND MODIFIED OPERATION EXAMPLE

Next, with reference to FIG. 15, the second modified operation exampleof the recording/reproducing apparatus 200 in the embodiment will bediscussed. FIG. 15 is a flowchart conceptually showing a flow of thesecond modified operation example. Incidentally, the same constitutionalelements and the same processes as those in the operation, explainedwith reference to FIG. 3 to FIG. 10, carry the same reference numeralsand the same step numbers, and the explanation thereof are omitted, asoccasion demands.

The second modified operation example is an operation example in whichthe dummy data is pre-recorded into the middle area 109 if therecording/reproducing apparatus 200 itself newly records the OPC patterninto the ODTA 114 of the L1 layer.

As shown in FIG. 15, the most outer circumferential address “E” of therecording area of the ODTA 114 which was used in the past (i.e. the mostouter circumferential address of the recording area of the ODTA 114 inwhich the OPC pattern or the like was recorded in the past) is obtained(step S301). More specifically, the most outer circumferential address“E” of the recording area of the ODTA 114 which has been already usedbefore the OPC pattern is recorded this time, is obtained.

Then, under the control of the CPU 354 or 359, it is judged whether ornot the ODTA 114 of the L1 layer is newly used (i.e. whether or not theOPC pattern or the like is newly recorded into the ODTA 114 of the L1layer) (step S302).

As a result of the judgment, if it is judged that the ODTA 114 of the L1layer is newly used (the step S302: Yes), a most outer circumferentialaddress (final address) “F” of the recording area of the newly-used ODTA114 in the L1 layer is obtained (step S303). Then, out of the middlearea 109 of the L0 layer, the address “B” next to the most outercircumferential address of the recording area in which the dummy data orthe like is already recorded, is obtained (step S304). Then, from adifference of the address “E” and the address “F”, a size “N” of thedata which can be recorded in the recording area between the address “E”and the address “F” is calculated (step S305). In other words, the sizeof the recording area which is newly used this time out of the ODTA 114in the L1 layer is calculated. For example, if the decrement addressmethod is adopted, N=F−E. On the other hand, if the increment addressmethod is adopted, N=E−F. Then, from the address “B” calculated in thestep S304, an address “G” of a position obtained by shifting to theouter circumferential side by the data size “N” is calculated (stepS306). For example, if the decrement address method is adopted, G=B−N.On the other hand, if the increment address method is adopted, G=B+N.Then, the predetermined dummy data is pre-recorded into the recordingarea from the address “B” to the address “G” out of the middle area 109in the L0 layer.

On the other hand, if it is judged that the ODTA 114 of the L1 layer isnot newly used (the step S302: No), the dummy data or the like is notpre-recorded into the middle area 109.

The aspect on the optical disc 100 at this time will be explained withreference to FIG. 16. FIG. 16 is a schematic conceptual viewschematically showing the relationship between each area and the addresson the optical disc 100 when the dummy data or the like is pre-recordedinto the middle area in the case where the ODTA 114 is newly used.

As shown in FIG. 16, out of the ODTA 114, the most outer circumferentialaddress of the recording area which has been already used before the useof the ODTA 114 this time, corresponds to the address “E”. Out of theODTA 114, the most outer circumferential address of the recording areawhich is newly used this time, corresponds to the address “F”. Out ofthe middle area 109, the address next to the most outer circumferentialaddress of the recording area in which the dummy data or the like ispre-recorded before the pre-recording this time, corresponds to theaddress “B”. The address of the position obtained by shifting to theouter circumferential side by the data size “N” from the positionrepresented by the address “B”, corresponds to the address “G”. Then,along with the new use of the ODTA 114 this time, the dummy data or thelike is newly pre-recorded into the recording area from the address “B”to the address “G”. In other words, the dummy data or the like havingthe same size as the used size of the ODTA 114 this time is newlypre-recorded into the middle area 109.

As explained above, according to the second modified operation example,it is possible to determined the recording area as being one portion ofthe middle area 109 in which the dummy data can be pre-recorded beforethe finalize process. Therefore, it is possible to receive theabove-mentioned various benefits. In particular, in accordance with thesize of the newly used ODTA 114, it is possible to determined therecording area as being one portion of the middle area 109 in which thepre-recording can be newly performed. Thus, there is no need to performunnecessary pre-recording, so that it is possible to reduce a processingload of the recording/reproducing apparatus 200.

Moreover, in the above-mentioned embodiment, the optical disc 100 isexplained as one example of the recording medium, and the recorder orplayer related to the optical disc 100 is explained as one example ofthe recording/reproducing apparatus. The present invention, however, isnot limited to the optical disc and the recorder thereof, and can beapplied to other various recording media, and the recorders or playersthereof, which support-high density recording or high transfer rate.

The present invention is not limited to the above-described embodiments,and various changes may be made, if desired, without departing from theessence or spirit of the invention which can be read from the claims andthe entire specification. A recording apparatus, a recording method, anda computer program for recording control, which involve such changes,are also intended to be within the technical scope of the presentinvention.

INDUSTRIAL APPLICABILITY

The recording apparatus, the recording method, and the computer programaccording to the present invention can be applied to a high-densityrecording medium, such as a DVD, for example, and also applied to aninformation recording apparatus, such as a DVD recorder. Moreover, theycan be applied to an information recording apparatus or the like, whichis mounted on or can be connected to various computer equipment forconsumer use or business use, for example.

1. A recording apparatus comprising: a recording device for recordingrecord information by irradiating laser light onto a recording mediumcomprising: (i) a first recording layer which is irradiated with thelaser light to thereby record therein the record information and whichhas a first area in which the record information is recorded; and (ii) asecond recording layer which is irradiated with the laser light throughthe first recording layer to thereby record therein the recordinformation and which has a second area whose edge on an innercircumferential side corresponds to an edge on an outer circumferentialside of the first area; and a controlling device for controlling saidrecording device to record pre-information in advance as the recordinformation, into an area portion as being one portion of the firstarea, at least other than an area portion having a size corresponding toa tolerance length, which indicates an acceptable range of a relativeposition shift between an address which is defined on the predeterminedposition in the first recording layer and an address which is related tothe predetermined position in the second recording layer, with the edgeon the outer circumferential side of the first area as a starting point.2. The recording apparatus according to claim 1, wherein the recordinformation is recorded into the second area through the first recordinglayer in which the record information is unrecorded.
 3. The recordingapparatus according to claim 1, wherein said controlling device controlssaid recording device to record the pre-information in advance, into anarea portion as being one portion of the first area, other than an areaportion having a size corresponding to a clearance length whichindicates a sum of (i) a spot radius of the laser light on the firstrecording layer in the case that the laser light is focused on thesecond recording layer and (ii) a relative eccentric shift of the firstand second recording layers or an acceptable range of the eccentricshift, in addition to the area portion corresponding to the tolerancelength.
 4. The recording apparatus according to claim 1, wherein saidrecording apparatus further comprises a converting device for convertingthe tolerance length to a recording unit of the record information, andsaid controlling device controls said recording device to record thepre-information in advance, into an area portion as being one portion ofthe first area, at least other than an area portion having a sizecorresponding to the tolerance length which is converted to therecording unit.
 5. The recording apparatus according to claim 4, whereinsaid converting device converts the tolerance length to the recordingunit of the record information, on the basis of correspondenceinformation which defines a correspondence relationship between thetolerance length and a size of the record information which can berecorded into an area portion having a size corresponding to apredetermined tolerance length.
 6. The recording apparatus according toclaim 5, wherein said converting device converts the tolerance length tothe recording unit of the record information, on the basis of at leastone of a plurality of correspondence information, in accordance with atleast one of a type of the recording medium and a position of the firstarea on the first recording layer.
 7. The recording apparatus accordingto claim 5, further comprising a storing device for storing thecorrespondence information.
 8. The recording apparatus according toclaim 5, wherein said converting device converts the tolerance length tothe recording unit of the record information, on the basis of thecorrespondence information recorded on the recording medium.
 9. Therecording apparatus according to claim 1, wherein if the recordinformation is recorded in the second area, said controlling devicecontrols said recording device to record the pre-information in advance,into an area portion as being one portion of the first area, at leastother than an area portion having a size corresponding to the tolerancelength, with a position of the first recording layer corresponding to anedge on the outer circumferential side of an area portion in the secondarea in which the record information is unrecorded as a starting point.10. The recording apparatus according to claim 1, wherein if the recordinformation is newly recorded into the second area, said controllingdevice controls said recording device to record the pre-information inadvance, into an area portion as being one portion of the first areahaving a size of an area portion in the second area in which the recordinformation is newly recorded, following the area portion in which thepre-recorded information is recorded in advance.
 11. The recordingapparatus according to claim 1, wherein said controlling device controlssaid recording device to record the pre-information in advance, exceptan area portion in the first area in which the pre-information isrecorded in advance.
 12. The recording apparatus according to claim 1,wherein the record information is recorded into the first recordinglayer in one direction, and the record information is recorded into thesecond recording layer in another direction different from the onedirection.
 13. The recording apparatus according to claim 1, wherein thetolerance length is set to substantially 40 μm in a radial direction ofthe recording medium.
 14. The recording apparatus according to claim 1,wherein the clearance length is set to substantially 84 μm.
 15. Arecording apparatus comprising: a recording device for recording recordinformation by irradiating laser light onto a recording mediumcomprising: (i) a first recording layer which is irradiated with thelaser light to thereby record therein the record information and whichhas a first area in which the record information is recorded; and (ii) asecond recording layer which is irradiated with the laser light throughthe first recording layer to thereby record therein the recordinformation and which has a second area in which the recordedinformation is recorded by irradiating the second area with the laserlight through an area portion of the first recording layer in which therecord information is unrecorded; and a controlling device forcontrolling said recording device to record pre-information in advanceas the record information, into an area portion as being one portion ofthe first area, at least other than an area portion having a sizecorresponding to a tolerance length, which indicates an acceptable rangeof a relative position shift between an address which is defined on thepredetermined position in the first recording layer and an address whichis related to the predetermined position in the second recording layer,with a position of the first recording layer corresponding to at leastone of an edge on an inner circumferential side and an edge on an outercircumferential side of an area portion in the second area in which therecord information is unrecorded as a starting point.
 16. A recordingmethod in a recording apparatus comprising: a recording device forrecording record information by irradiating laser light onto a recordingmedium comprising: (i) a first recording layer which is irradiated withthe laser light to thereby record therein the record information andwhich has a first area in which the record information is recorded; and(ii) a second recording layer which is irradiated with the laser lightthrough the first recording layer to thereby record therein the recordinformation and which has a second area whose edge on an innercircumferential side corresponds to an edge on an outer circumferentialside of the first area, said recording method comprising: a firstcontrolling process of controlling said recording device to record therecord information; and a second controlling process of controlling saidrecording device to record pre-information in advance as the recordinformation, into an area portion as being one portion of the firstarea, at least other than an area portion having a size corresponding toa tolerance length, which indicates an acceptable range of a relativeposition shift between an address which is defined on the predeterminedposition in the first recording layer and an address which is related tothe predetermined position in the second recording layer, with the edgeon the outer circumferential side of the first area as a starting point.17. A recording method in a recording apparatus comprising: a recordingdevice for recording record information by irradiating laser light ontoa recording medium comprising: (i) a first recording layer which isirradiated with the laser light to thereby record therein the recordinformation and which has a first area in which the record informationis recorded; and (ii) a second recording layer which is irradiated withthe laser light through the first recording layer to thereby recordtherein the record information and which has a second area in which therecorded information is recorded by irradiating the second area with thelaser light through an area portion of the first recording layer inwhich the record information is unrecorded, said recording methodcomprising: a first controlling process of controlling said recordingdevice to record the record information; and a second controllingprocess of controlling said recording device to record pre-informationin advance as the record information, into an area portion as being oneportion of the first area, at least other than an area portion having asize corresponding to a tolerance length, which indicates an acceptablerange of a relative position shift between an address which is definedon the predetermined position in the first recording layer and anaddress which is related to the predetermined position in the secondrecording layer, with a position of the first recording layercorresponding to at least one of an edge on an inner circumferentialside and an edge on an outer circumferential side of an area portion inthe second area in which the record information is unrecorded as astarting point.
 18. A computer program product in a computer-readablemedium for tangibly embodying a program of instructions executable by acomputer provided in a recording apparatus, to make the computerfunction as a controlling device, said recording apparatus comprising: arecording device for recording record information by irradiating laserlight onto a recording medium comprising: (i) a first recording layerwhich is irradiated with the laser light to thereby record therein therecord information and which has a first area in which the recordinformation is recorded; and (ii) a second recording layer which isirradiated with the laser light through the first recording layer tothereby record therein the record information and which has a secondarea whose edge on an inner circumferential side corresponds to an edgeon an outer circumferential side of the first area; and said controllingdevice for controlling said recording device to record pre-informationin advance as the record information, into an area portion as being oneportion of the first area, at least other than an area portion having asize corresponding to a tolerance length, which indicates an acceptablerange of a relative position shift between an address which is definedon the predetermined position in the first recording layer and anaddress which is related to the predetermined position in the secondrecording layer, with the edge on the outer circumferential side of thefirst area as a starting point.
 19. A computer program product in acomputer-readable medium for tangibly embodying a program ofinstructions executable by a computer provided in a recording apparatus,to make the computer function as a controlling device, said recordingapparatus comprising: a recording device for recording recordinformation by irradiating laser light onto a recording mediumcomprising: (i) a first recording layer which is irradiated with thelaser light to thereby record therein the record information and whichhas a first area in which the record information is recorded; and (ii) asecond recording layer which is irradiated with the laser light throughthe first recording layer to thereby record therein the recordinformation and which has a second area in which the recordedinformation is recorded by irradiating the second area with the laserlight through an area portion of the first recording layer in which therecord information is unrecorded; and said controlling device forcontrolling said recording device to record pre-information in advanceas the record information, into an area portion as being one portion ofthe first area, at least other than an area portion having a sizecorresponding to a tolerance length, which indicates an acceptable rangeof a relative position shift between an address which is defined on thepredetermined position in the first recording layer and an address whichis related to the predetermined position in the second recording layer,with a position of the first recording layer corresponding to at leastone of an edge on an inner circumferential side and an edge on an outercircumferential side of an area portion in the second area in which therecord information is unrecorded as a starting point.